summaryrefslogtreecommitdiff
path: root/kernel/fork.c
diff options
context:
space:
mode:
authorAlan Cox <alan@redhat.com>2008-10-13 10:37:26 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-13 09:51:40 -0700
commit9c9f4ded90a59eee84e15f5fd38c03d60184e112 (patch)
tree925a7f7c30136477b3f8551123fd86b355fd60fb /kernel/fork.c
parent348eb12e5598be97400c749d3d93a71856ae0b2b (diff)
tty: Add a kref count
Introduce a kref to the tty structure and use it to protect the tty->signal tty references. For now we don't introduce it for anything else. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/fork.c')
-rw-r--r--kernel/fork.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 7ce2ebe84796..30de644a40c4 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -802,6 +802,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->leader = 0; /* session leadership doesn't inherit */
sig->tty_old_pgrp = NULL;
+ sig->tty = NULL;
sig->utime = sig->stime = sig->cutime = sig->cstime = cputime_zero;
sig->gtime = cputime_zero;
@@ -838,6 +839,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
void __cleanup_signal(struct signal_struct *sig)
{
exit_thread_group_keys(sig);
+ tty_kref_put(sig->tty);
kmem_cache_free(signal_cachep, sig);
}
@@ -1227,7 +1229,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->nsproxy->pid_ns->child_reaper = p;
p->signal->leader_pid = pid;
- p->signal->tty = current->signal->tty;
+ tty_kref_put(p->signal->tty);
+ p->signal->tty = tty_kref_get(current->signal->tty);
set_task_pgrp(p, task_pgrp_nr(current));
set_task_session(p, task_session_nr(current));
attach_pid(p, PIDTYPE_PGID, task_pgrp(current));